Traffic-related particle emissions, not resulting from exhaust gases, but rather from abrasion of brakes, tires, clutches, road coverings, etc. and also from resuspension of road dust, contribute substantially to air pollution. Exhaust gas particle emissions are expected to decrease as a result of stricter limiting values, but the other traffic-related particle emissions will increase as a result of greater traffic volume and could come into the focus of future regulations. According to data of the German Federal environmental office, it may be expected that exhaust gas particle emissions in the year 2020 will still make up approximately 18% of all traffic-related fine dust emissions, wherein the term fine dust refers to the particles, which are considered to be especially harmful to health, having aerodynamic diameters less than 10 μm. The remaining 82% are emissions not caused by exhaust gas, but rather by wear. This shows the increasing significance of the particle emissions, which are not caused by exhaust gas.
Technologies, for example, shields, fans, and dust collectors, are known especially for reducing brake dust emissions.
WO 03/035206 A2 discloses a motor vehicle having a particle analyzer installed therein. This particle analyzer, which is supposed to also be able to count the particles, is a very complex device, which is only used for test travel.
U.S. Pat. No. 5,517,298 A discloses a device for measuring the movement of transparent gases or liquids by illuminating entrained small solid or liquid particles and measuring the velocity thereof by velocimetry.
DE 10 329 961 A1 discloses an integrated fine dust suction device for vehicles, using which fine dust can be filtered out of the ambient air and collected for scientific studies and which can also be analyzed during the collection using an aerosol spectrometer as a dust meter, wherein the measured data can be relayed via radio.
Motor vehicles have also already been proposed, wherein the ambient air is to be filtered of fine dust during travel.
Thus, DE 20 2006 019 335 U1 discloses a fine dust suction device for vehicles, wherein the fresh air supplied to the vehicle interior can be filtered of fine dust, but which the fine dust content in the ambient air can also be reduced, in order to maintain fine dust limiting values prescribed by law.
DE 20 2006 004 522 U1 discloses a fine dust filter, which operates using electrical and/or magnetic separation, and which is arranged between an air intake grill and a radiator, to filter the ambient air flowing through therein of fine dust, as well as that fine dust which has been emitted or resuspended by other vehicles.
DE 20 2005 005 673 U1 discloses an external air filter, which is mounted under a bumper, for motor vehicles for general reduction of air pollution.
Such systems could only effectively reduce fine dust in the environment if they have been installed in a very large number of vehicles, and the effort for cleaning the many filters and/or for disposing of the collected dust would also be extreme, particularly also because comparatively coarse dust, which is not actually harmful, would be collected and the filters would fill up rapidly.
DE 10 2009 054 194 A discloses a vehicle having a heads-up display and a camera introduced into the beam path thereof, from the image data of which rain or dirt on the windshield can also be recognized.
JP H09 242 500 A discloses an environmental measuring vehicle having a dust concentration sensor arranged on the roof.